Inhomogeneities in the Universe

This lecture explores the inhomogeneities in the Universe, focusing on gravitational instability, time evolution, and the formation of structures. It discusses the evidence of structures, the density contrast, and the impact of density fluctuations on the evolution of the Universe. Key topics include the temperature of the Cosmic Microwave Background, the first atoms formed after the Big Bang, and the detection of the CMB. The lecture also covers the growth of structures, the SZ-effect, and the constraints provided by CMB anisotropies.